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[Fibrosarcoma after silicone breast augmentation: is there a connection?].

We describe a 42-year-old woman in whom bilateral fibrosarcoma of the breast was diagnosed 15 years after bilateral breast augmentation with silicone implants. 3 years prior to admission the implants were replaced and 2 years prior to admission mammography showed a nodule in the left breast which biopsy showed to be fibrosarcoma. The implants were removed from both breasts and she was given chemotherapy but later that year underwent bilateral mastectomy. Despite chemotherapy, as well as adjuvant radiotherapy, the disease progressed, with involvement of the lungs and the skin of the left hemithorax. She was admitted repeatedly for severe anemia caused by bleeding from the malignant skin lesions, and died less than 2 years after diagnosis of the disease. Not all reports in the literature find a significant connection between silicone implants and subsequent development of breast cancer, but there are reports that do connect them. Breast fibrosarcoma is not significantly more frequent after silicone augmentation, but still there is controversy as to whether there is a connection between silicone implants and breast malignancy. In the patient we present, the prolonged exposure to silicone may have been a predisposing factor for the development of bilateral fibrosarcoma, since other known risk factors for breast cancer were denied.

Adult↗

Results of transurethral injection of silicone micro-implants for females with intrinsic sphincter deficiency.

PURPOSE: We evaluated the medium term efficiency of silicone micro-implants injected in women with intrinsic sphincter deficiency. MATERIALS AND METHODS: A total of 21 women with intrinsic sphincter deficiency underwent transurethral injection of silicone micro-implants between August 1996 and February 1997. Each patient was assessed preoperatively by questionnaire, physical examination and urodynamic study. The results were evaluated by questionnaire at 1 month, and 1 and 2 years after silicone injection. The outcome was classified as dry in all circumstances, improved or failure. RESULTS: All patients (median age 68 years, range 46 to 83) had undergone previous anti-incontinence or prolapse surgeries. At 1 month 2 patients (10%) were dry and 9 (42%) were improved, and treatment failed in 10 (48%). At 1 year (median 16 months, range 14 to 22) 2 cases (10%) were classified as dry, 8 (38%) improved and 11 (52%) failures. At last followup (median 31 months, range 24 to 34) 4 cases (19%) were classified as dry, 6 (29%) improved and 11 (52%) failures. None of the 6 patients with bladder neck hypermobility was dry. CONCLUSIONS: Our results of silicone transurethral injection are disappointing but comparable to other bulking agents without a time dependent decrease in efficiency. The use of silicone micro-implants is an alternative for the treatment of intrinsic sphincter deficiency in patients without bladder neck hypermobility and in whom the sling procedure has failed.

Aged↗

[Results of treating retinal redetachment following silicone oil removal].

PURPOSE: The assessment of anatomical and functional results in the treatment of retinal redetachment after silicone oil removal (OR). MATERIALS: Between November 1992 and October 1996 silicone oil was removed from 104 eyes (98 patients). Retinal redetachment occurred in 11 eyes, mostly within 1 month after silicone oil removal. METHOD: Revitrectomy with silicone oil tamponade was performed in all cases. RESULTS: Retinal attachment was achieved in 8 cases (73%) postoperatively, but only three eyes achieved the same visual acuity as before SOR. Functional results occurred worse than previous SOR in other patients. Visual acuity 1/60 or better was achieved in 6 cases. CONCLUSIONS: Our observations demonstrate that revitrectomy with silicone oil endotamponade is an effective treatment for retinal redetachment after SOR, even if functional results are not as good as anatomical.

Humans↗

[Effect of sodium chloride on elasticity of silicone matrices].

An increase in the availability of the active ingredient from silicone matrices can be achieved by using sodium chloride as the filler. An addition of sodium chloride also influences the mechanical properties of silicone systems. The temperature dependence of real Young's model E' of addition silicone systems with sodium chloride was measured. With increasing NaCl concentration in the silicone system, the values of Young's module E are increased. The increase is also influenced by the particle size of NaCl. The values of the module are moderately increased also with increasing temperature, which corresponds to the kinetic theory of caoutchouc elasticity. A significant increase in E takes place at NaCl concentrations higher than 20%. With a 50% NaCl content in the system, E is increased approximately 3.5 times in comparison with an unfilled sample. Various theories of elastic behaviour of composites can be employed for the description of the effect of the filler on the mechanical properties of silicone systems under small deformations. The effect of chloride is best described by the relation proposed by Nielsen. The value of the constant A in Nielsen's relation, dependent on the shape of the filler particles and Poisson's constant of the unfilled matrix, decreases with increasing particle size. With a change in particle size, a certain change in particle shape takes place. Hydrodynamic theory provides good results for sodium chloride particle size of 102.5 microns, but for particle sizes of 20 microns and 60 microns it is less successful than Nielsen's relation.

Chemical Phenomena↗

Blood and tissue silicone in extracorporeal circulation.

A new method for the determination of blood and tissue contents of silicone by atomic absorption spectrophotometry is described. Silicone was found in the blood, probably as droplets, in each of 14 patients undergoing open-heart surgery with the aid of a bubble oxygenator. In five fatal cases the brains and kidneys contained silicone. Although the clinical significance of the silicone embolization is unclear precautions should be taken to reduce the release of silicone from the extracorporealoxygenating devices.

Aged↗

Bonding of silicone prosthetic elastomers to three different denture resins.

PURPOSE: The aim of this study was to evaluate the interfacial bond strength between different types of silicone facial elastomers and denture resins. MATERIALS AND METHODS: The facial materials studied were Cosmesil and Ideal, whereas SR 3/60, SR 3/60 Quick, and Triad were included in the denture resins group. The "overlap-joint" model was used to evaluate the bond strength, and the samples were placed in tension until failure. The bonding surfaces were treated with a primer. Ten samples for each silicone/resin group were tested. The results were subjected to two-way analysis of variance and Tukey's test for comparison. RESULTS: The bond strength was affected by the type of silicone elastomer and denture resin. An interaction between them was also noted. The bond strength ranged from 0.03 to 0.23 MPa. CONCLUSION: Cosmesil condensation-type silicone always showed higher bond strength with the three different types of denture resins compared to Ideal addition silicone, keeping other variables associated with the silicone-resin bond fixed.

Acrylic Resins↗

[Can the use of intraocular silicone oil increase the risk of sympathetic ophthalmia?].

CLINICAL CASES: We report two cases of SO (sympathetic ophthalmia) among 1,456 vitrectomies and 255 silicone oil injections performed since 1990. In both patients intraocular silicone oil was used. Both cases were clinically documented and one pathologically demonstrated. DISCUSSION: No cases were reported among vitrectomies without silicone oil. We found a longer delay between injury and the onset of the disease in comparison to the literature. Pathological findings confirmed a foreign body granulomatous reaction. Chronic inflammation caused by silicone oil might be involved in the development of SO. Larger series are necessary to establish a possible relationship between silicone oil and SO.

Aged↗

Droplets on posterior surface of intraocular lens in silicone oil filled eye.

Silicone oil adherence to silicone IOLs after silicone oil removal is a known complication in pseudophakic patients. Droplet removal is difficult and may require IOL exchange. We describe two cases in which silicone oil droplets were observed early in the postoperative period in PMMA pseudophakic eyes and disappeared during silicone oil-fluid exchange--a phenomenon that has not been reported earlier in human PMMA pseudophakic eyes.

Drainage↗

[Cataract surgery in eyes after vitrectomy filled with long-term silicone oil tamponade].

PURPOSE: Evaluation of the results of cataract extraction in eyes filled with silicone oil. MATERIAL AND METHODS: Twenty-nine eyes of 29 patients underwent cataract extraction without intraocular lens implantation, in eyes after vitrectomy filled with silicone oil. The average time of silicone oil tamponade was 3.5 years (range from 10 months to 6 years). The mean follow-up was 26.1 +/- 17.5 months. RESULTS: Useful visual acuity was achieved in 55% eyes. The main complication was the increased intraocular pressure, which appeared in 38% eyes. CONCLUSION: Cataract surgery in eyes with long-term silicone oil tamponade get benefit, because it enables restoring the useful visual acuity. More advanced retinal pathology and silicone oil tamponade increase the number of complications.

Adult↗

[Evaluation of the results of cataract surgery in eyes after silicone oil removal].

PURPOSE: To evaluate the results of cataract surgery in eyes after silicone oil removal and comparison of surgical technics. MATERIAL AND METHODS: Eighty-four eyes of 80 patients underwent cataract extraction and IOL implantation after vitrectomy with silicone oil, after its removal. In 50 eyes of group A cataract surgery was performed using the ECCE procedure, in 20 eyes of group B-phacoemulsification was done and in 14 eyes of group C cataract surgery was performed simultaneously with silicone oil removal. Ten eyes of the control group K underwent cataract extraction without IOL implantation. The follow-up was 15.5 +/- 11.2 months. RESULTS: Visual acuity of 6/60 or better was achieved in 65% of eyes. Statistically significant improvement in visual acuity was observed after cataract surgery, compared to the results after vitrectomy in the study group and in the control group. The most frequent complication was posterior capsule opacification, which occurred in 47 eyes (54.6%). CONCLUSIONS: Cataract surgery and IOL implantation in eyes after vitrectomy with silicone oil is safe and achieved visual acuity is similar or better, than before cataract formation. The usefulness of combined cataract surgery and silicone oil removal requires further studies.

Adult↗

[Effect of fibrin on nerve regeneration in a silicone chamber].

When regenerating from an injury, fluid containing nerve growth-promoting components such as the nerve growth factor (NGF) will accumulate around the stump of a cut nerve within 24 hours. It has been found that this fluid also contains fibrin. To evaluate the effect of fibrin on nerve regeneration, we cut both facial nerves of 40 guinea pigs and sutured both ends of the nerve stumps to silicone tubes. The distance between the stumps were kept at around 8 mm in the silicone chamber. Autogenous fibrin isolated from the blood of each guinea pig was injected into the silicone chamber on the left side, while lactate Ringer's solution was injected into the silicone chamber on the right side as a control. The status of nerve regeneration in both sides of the silicone chambers were later evaluated at 3 and 5 weeks. Histological study revealed that after regeneration for 3 weeks, the total axon number and the fascicular number increased significantly in the fibrin-filled chamber. However, after 5 weeks, there was no significant difference in nerve regeneration between the two groups.

Animals↗

Hypertrophic sternal scars: silicone gel sheet versus Kenalog injection treatment.

A prospective, randomized trial was designed to compare the standard Kenalog injection of established hypertrophic sternal scars with topical silicone gel sheets (Spenco). Fourteen poststernotomy cardiac patients with symptomatic scars were randomized to treatment in one-half of the scar with Kenalog injection. Simultaneously, the other half of the scar received the silicone gel sheet. The standard Kenalog injection used was 40 mg/ml x 1 cc, mixed with 1 cc of 1% Xylocaine with epinephrine. The gel sheets were worn continuously for 12 hours for 12 weeks. Pretreatment and posttreatment photographs were compared for color and appearance by blindfolded observers. Scar measurements (length, width, and height) were taken weekly in each area, and the patients were asked to rank their symptoms within each half as worse, the same, or better. The primary outcome of patient preference was analyzed sequentially, and the recruitment was terminated after 11 patients had completed the study, 10 of whom favored the silicone gel treatment (p < 0.05). Three patients remained in the treatment phase at the time of termination and completed the study subsequently. For the total sample of 14 subjects, 11 preferred the silicone gel, 1 expressed no preference, and 2 preferred the injection. The average time to improvement was 3.9 +/- 0.62 days (gel) versus 6.8 +/- 1.86 days (Kenalog). This study demonstrates that silicone gel sheets provide earlier symptomatic relief and a more aesthetic scar and are the preferred treatment of patients with symptomatic hypertrophic sternal scars.

Administration, Topical↗

Rupture of silicone gel breast implants and symptoms of pain and fatigue.

OBJECTIVE: To compare symptoms of women with silicone gel breast implants and women with chronic fatigue syndrome (CFS), and to study the effect of rupture of the silicone implant. METHODS: Five hundred readers of the Dutch silicone breast implant support group magazine were asked to respond if they had been informed by the surgeon about the silicone implant status at operation, and to answer questions about symptoms of CFS. Their complaints were compared with those of 100 female patients with CFS and 40 female controls. RESULTS: The questionnaires were returned by 319 women. Of these, 227 had symptoms of debilitating chronic fatigue. The patterns of symptoms differed from those in patients with CFS. An analysis of the relation between integrity of the implants and the symptoms could be carried out in 176 women, and 74% of these latter women reported ruptured implants. Significantly more women with ruptured implants than those with intact implants had debilitating chronic fatigue (75% vs 51%), postexertional malaise > 24 h (77% vs 51%), impaired short term memory (58% vs 38%), and multi-joint pain (77% vs 60%). CONCLUSION: Women with silicone breast implants often report severe pain and chronic fatigue. Rupture of the implant is associated with an increase in symptoms of pain and chronic fatigue.

Adult↗

Bonding of silicone extra-oral elastomers to acrylic resin: the effect of primer composition.

Silicone elastomer is bonded to acrylic resin in many facial or oro-facial prostheses. The silicone elastomer/acrylic resin bond has been reported to be insufficient and primers have been used to enhance the bond. This study investigated the bond strength of silicone elastomer to acrylic resin using different types of primers. The extra-oral silicone elastomers studied were Cosmesil and Ideal. The "overlap-joint" model was used to evaluate the bond strength and the samples were stretched until fracture. The bonding surfaces were treated with a primer. The control primer was Cosmesil and the others a mixture of Cosmesil/Z-6020 and Cosmesil/A-174 in 50/50 v/v ratio. The bond strength ranged from 0.026 MPa to 0.219 MPa. The results obtained in this work led to the conclusion that the most critical parameter allowing the efficient performance of a primer is the compatibility and affinity of its composition with the selected silicone elastomer.

Acrylic Resins↗

[Modification of silicone oil removal via limbus of corneal with aphakia].

OBJECTIVE: To introduce a simplified method to remove silicone oil via limbus of corneal after previous lensectomy-vitrectomy. METHODS: Fifty-one eyes received the modified procedures to eliminate silicone oil via one pars plana or limbus incision after previous lensectomy-vitrectomy. Local anesthesia was performed with 25G syringe needle through pars plana or corneal limbus infusion and super limbus incisions to eliminate silicone oil. RESULTS: All operations were primarily successful in eliminating silicone oil. The complications occurred in all the patients with the early low intraocular pressure, in 4 (4/51, 7.8%) eyes with retinal detachment, and in 2 (2/51, 3.9%) eyes with less bleeding at the point of puncture. The visual acuity was significantly improved after the procedure (P < 0.05) in patients with stable retinal reattachment. CONCLUSION: The procedure via one pars plana and limbus or limbus incision after previous lensectomy-vitrectomy is useful in removing the silicone oil tamponade in aphakic eyes because of its simplicity, good curative effect, and fewer complications.

Adolescent↗

[Are silicone breast prostheses dangerous?].

Since 1964 silicone breast prostheses have been implanted in 5 million women for breast reconstruction after cancer operations, to correct congenital deformities and for cosmetic reasons. There is no evidence in the literature of a correlation between silicone implants and breast cancer. Some authors claim that silicone implants reduce the reliability of mammography. Autoimmune diseases in patients with silicone mammary implants are reported in less than 40 cases. Most of these are localized or systemic scleroderma. An association with silicone implants has been suggested, but this suggestion has not been confirmed by scientific data.

Europe↗

["AID" implanted in eyes with silicone oil tamponade].

OBJECTIVE: To summarize the clinical results of the artificial iris diaphragm (AID implantation for eyes with silicone oil longstanding tamponade. METHODS: In this study the operation indications results and complications of 11 consecutive cases of artificial iris diaphragm implantation for eyes with silicone oil longstanding tamponade were studied. RESULTS: In all of the 11 primary ocular disorder cases, 7 cases (7/11) were serious ocular trauma, 2(2/11)cases were diabetic retinopathy with traction retinal detachment, 1 case (1/11) was recurrent retinal detachment with complicated PVR, and 1 case (1/11) was Coats disease; The silicone oil was retained completely behind the surface of artificial iris diaphragm in 7(7/11) of all the 11 cases in which no visual acuity was affected The complications were low intraocular pressure IOP and heavy fibrosis on the surface of artificial iris diaphragm. CONCLUSION: Open type artificial iris diaphragm implantation in eyes with longstanding silicone oil tamponade can effectively prevent the silicone oil from cotacting the cornea causing complication by spontaneously blocking and rescuing anterior chamber fluid circulation.

Adolescent↗

[Accumulation pattern of dry matter, nitrogen, phosphorus, potassium and silicon in rice genotypes and their relationships].

The accumulation of dry matter, nitrogen, phosphorus, potassium and silicon in 30 rice genotypes and their relationships under field condition were studied. The results showed that dry matter accumulated at ripening stage linearly increased with increase of nitrogen, phosphorus, potassium and silicon accumulation with highly significant correlation coefficients at both early and late season. At the same time balance of nitrogen, phosphorus, potassium and silicon accumulation was beneficial for dry matter accumulation, which linearly increased with increase of nutrient balance index and decreased with increase of nutrient deviation index. The nitrogen, phosphorus, potassium and silicon were accumulated at the rate of 3.76:1:4.55:7.10 at early season and 2.88:1:4.54:8.09 at late season. During growth period, dry matter accumulation was the highest at middle stage, then late stage and early stage. But nitrogen accumulation was the highest at early stage, then middle stage and late stage. The dry matter accumulated before heading was mainly distributed in stem and leaf sheath, with the highest ratio of stem and leaf sheath to total dry matter at heading stage. In contrast, nitrogen accumulated before heading was mainly distributed in leaf blade, and the ratio of nitrogen in leaf blade to total nitrogen was higher than that of dry matter at either growth stages. Dry matter, nitrogen, phosphorus accumulated at ripening stage were mainly distributed in panicle with rates of 58.01%, 66.42% and 70.06%, respectively. But potassium accumulated at ripening stage was mainly distributed in stem and leaf sheath with the rate of 62.08%. Silicon was largely distributed in stem and leaf sheath at early season with the rate of 43.11%, but distributed largely in panicle at late season with the rate of 46.99%.

Genotype↗